Abstract

Introduction: Anxiety is the most common psychological response of women to labor. The aim of the present systematic review was to evaluate and summarize the available clinical evidence on the anxiolytic effects of aromatherapy during the first stage of labor. Methods: Electronic databases including: Cochrane Library, MEDLINE/ PubMed, Scopus, CINAHL, SID, Iran Doc, ProQuest, and Google Scholar were searched up to Sep10, 2017 with the keywords of 'aroma*', 'aromatherapy', 'essential oil', 'anxiety', and ' labor '. The risk of bias in the included studies was assessed using the Cochrane Collaboration's 'Risk of bias' tool. The results were reported qualitatively. Results: A total of 14 published papers and 2 unpublished papers were retrieved which met the inclusion criteria. The studies were conducted in Iran, Egypt, Korea, and Italy. Essential oils had been used were lavender in 5 articles, rose, clary sage, geranium and frankincense in 3 articles, chamomile, bitter orange, sweet orange and peppermint in 2 articles, mandarin orange, jasmine and clove in 1 article. A majority of the studies suggested a positive effect of aromatherapy in reducing women's anxiety during the first stage of labor. Conclusion: It is recommended that aromatherapy could be applied as a complementary therapy for reducing anxiety during the first stage of labor, but methodologically rigorous studies should be conducted in this area.

KEYWORDS:

On the initial search, 1415 articles were retrieved. After excluding 494 duplicates and 900 irrelevant articles, 21 articles remained for further full text screening. A total number of 5 studies were excluded at this stage, 2 studies were duplicate publications, 2 studies contained overlapping data, and 1 study was not original literature. Eventually, 16 studies- were verified to meet our inclusion criteria. Two studies, were master’s theses and 14 were published in peer-reviewed journals. The full text of one study could not be retrieved and the relevant data were extracted from its abstract. The findings of one study were presented in three separate reports.- The systematic study selection is presented in the form of a flow diagram ().

Random sequence generation was adequately described by description in seven trials. Six studies,,-, referred to a random number table and one study used computer generated randomization for sequence generation. The other trials did not describe the sequence generation process. Allocation concealment was adequate in one study whose allocation was concealed by using envelopes. The other trials were rated ‘unclear’, as they did not have clear descriptions of their method of allocation concealment. All the studies included had a high risk of bias for blinding of the participants, care providers and outcome assessors All the studies were judged to have a low risk of bias for incomplete outcome data; fifteen- had no participant losses, or the missing data were balanced in numbers across groups and one study was performed an ‘intention-to-treat’ analysis. As far as we could see, all studies included were free of selective outcome reporting and other potential sources of bias. See ; 'Risk of bias' graph and 'Risk of bias' summery of included studies.

Random sequence generation was adequately described by description in seven trials. Six studies,,-, referred to a random number table and one study used computer generated randomization for sequence generation. The other trials did not describe the sequence generation process. Allocation concealment was adequate in one study whose allocation was concealed by using envelopes. The other trials were rated ‘unclear’, as they did not have clear descriptions of their method of allocation concealment. All the studies included had a high risk of bias for blinding of the participants, care providers and outcome assessors All the studies were judged to have a low risk of bias for incomplete outcome data; fifteen- had no participant losses, or the missing data were balanced in numbers across groups and one study was performed an ‘intention-to-treat’ analysis. As far as we could see, all studies included were free of selective outcome reporting and other potential sources of bias. See ; 'Risk of bias' graph and 'Risk of bias' summery of included studies.